Abstract — When designing linkage driven underactuated

robotic finger, many parameters needs to be satisfied in order to

produce robust robotic hand capable of withstanding industrial

environment and capable of fulfilling all needs of robotic

assembly in terms of precision and dexterity. For this study,

four-bar linkage mechanisms are used to drive underactuated

robotic finger and design parameter that will be addressed is

transmission performance. Optimization method used for

obtaining length of links of four-bar mechanism, based on

transmission performance is shown. Freundenstein’s analytic

method for four-bar linkage function generation, is chosen, and

calculated link lengths are to be used for acquiring parameter

called transmission defect, parameter that is objective function

to be minimized in this optimization process. Maximizing

transmission performance, leads to increase of the transmitted

torque from the actuated joints to the underactuated joints

through transmission mechanism. This paper presents design

and kinematic analysis of three degrees of freedom (3-DoF)

underactuated robotic finger with linkage driven mechanism for

CMSysLab robotic hand.

Index Terms—Robotic Assembly, Robotic Hand, Design;

Transmission performance, Transmission defect;

I. INTRODUCTION

Concept of underactuation has many advantages and

because of these advantages it is used in many branches of

industry. In robotics, it has application in many robotic hands

that are designed for laboratory and industrial setting. These

hands utilize different mechanisms that transmit the actuation

torque to the underactated joints. Two most popular and

widely used concepts for underactuated mutlifingered robot

hands, [1], are tendon and linkage based transmission

mechanisms, shown on Fig.1.

Fig. 1. Tendon and linkage based transmission mechanisms used in

underactuated robotic finger. [2].

For our study we have chosen linkage based mechanism

because of it’s rigidity which makes these mechanisms more

predictable, more accurate and more controllable.

PhD student Lazar Matijašević is with the Faculty of Mechanical

Engineering, University of Belgrade, Kraljice Marije 16, 11120 Belgrade,

Serbia (e-mail: lmatijasevic@mas.bg.ac.rs). Full Professor Petar B. Petrović is with the Faculty of Mechanical

Engineering, University of Belgrade, Kraljice Marije 16, 11120 Belgrade,

Serbia (e-mail: pbpetrovic@mas.bg.ac.rs).

These, linkage based mechanisms, are suitable for bigger

grasping forces, which is mandatory in assembly operations

in industrial setting.

Simplified sketch of underactuated 3-DOF finger with

linkage driven mechanism is shown on Fig. 2.

Fig. 2. Representation of 3-DOF finger with linkage driven mechanism.

Transmission mechanism of 3-DOF underactuated finger

shown on Fig. 2 consists of two four-linkage mechanisms,

O3-O2-P2-P3 and O2-O1-P1-P2’, interconnected with rigid

triangular shaped rocker, O2- P2- P2’.

Requirements for the design of linkage based robotic finger

must be met in order to ensure desired motion. Many different

optimization algorithms are devised in order to obtain better

characteristics of transmission mechanisms. Some of those

characteristics are reduced power consumption, reduced

structure errors for different mechanisms, force transmission,

weight, size and many more. According to aforementioned

characteristics there are many design parameters to be met in

order to design robust and dexterous robotic hand that can

fulfill all requirements of robotic assembly in industrial

setting. Focus of this paper will be on transmission

performance optimization. Proposed method of optimization

focuses on introducing and minimizing parameter named

transmission defect and, based on its minimal value,

determining optimal value of lengths of four-bar mechanism

links.

II. GENERAL CONCEPT OF ANALYSIS

Variety of useful mechanisms can be formed from a four-

link mechanism, shown on Fig. 3, through slight variations,

such as changing the character of the pairs, proportions of

links, etc. In this paper, two four-bar linkage mechanisms [3],

connected with rocker are used for movement and force

transmission on phalanx of the underactuated robotic finger.

A. Freudenstein’s equation

Analytical method of kinematic synthesis for four-bar

linkage mechanism used in this paper is Freundenstein’s

Four-bar Linkage Mechanism Optimization for

Linkage Driven Underactuated Robotic Finger Lazar Matijašević, PhD Student, Petar B. Petrović, Full Professor

ROI 1.2.1

method [4]. Using this method, it is possible to calculate link

lengths that accommodate generated function. Also this

method is useful in calculating link lengths of four-bar

linkage mechanisms because we can use only three positions

of mechanism to solve Freundenstein’s equation by solving

system of three linear equations as will be shown. On Fig 3.,

a typical four-bar linkage mechanism is shown.

Fig. 3. Representation of four-bar linkage mechanism.

Following parameters are presented on Fig. 3 of O1O2AB

four-bar linkage mechanism:

- Fixed link O1O2, (l1), also a phalange of robotic finger,

- Input link O2A, (l2),

- Coupler link AB, (l3),

- Output link BO1, (l4),

- Orientation of the input and output link is defined by

the angles they construct with x axis and those are

input angle ϴ1 and output angle ϴ2.

Using three position synthesis method allows us to solve

equation by generating two pairs of prescribed coordinated

movement, shown in (1), of the input and output link.

(𝜃112, 𝜃2

12) , (𝜃1

23, 𝜃223

) . (1)

From position 1 to position 2 change in the angle ϴ1 is

given by ϴ112 and corresponding change in the angle ϴ2 is

given by ϴ212. Same stands for movement from position 2 to

position 3. These are two pairs of prescribed movement.

In three position synthesis using Freundenstein’s method,

we assume the values of ϴ1 corresponding to the first

configuration (ϴ11) and the value of ϴ2 corresponding to first

configuration (ϴ21). Using inputs from (1) we can write:

𝜃12 = 𝜃1

1 + 𝜃112 ;

𝜃22 = 𝜃2

1 + 𝜃212 ,

(2)

and:

𝜃13 = 𝜃1

2 + 𝜃123 ;

𝜃23 = 𝜃2

2 + 𝜃223 .

(3)

Freundenstein’s equation, which is displacement equation

for this planar mechanism, must be valid for all three sets of

aforementioned input and output angles. Coordinates of

points A and B are:

𝑥𝐴 = 𝑙1 + 𝑙2 cos 𝜃1 ; 𝑦𝐴 = 𝑙2 sin 𝜃1 ,

𝑥𝐵 = 𝑙4 cos 𝜃2 ; 𝑦𝐵 = 𝑙4 sin 𝜃2 .

(4)

Length of the coupler link 3 is:

𝑙32 = (𝑥𝐴 − 𝑥𝐵)2 + (𝑦𝐴 − 𝑦𝐵)2 . (5)

Substitution of (4) in (5) yields:

cos(𝜃1 − 𝜃2) =𝑙1𝑙4

cos 𝜃1 −𝑙1𝑙2

cos 𝜃2 +

+𝑙12 + 𝑙2

2 − 𝑙32 + 𝑙4

2

2𝑙2𝑙4 .

(6)

We now introduce term design parameter Di, i=1,2,3,

described as follows:

𝐷1 =𝑙1𝑙4

; 𝐷2 =𝑙1𝑙2

; 𝐷3 =𝑙12 + 𝑙2

2 − 𝑙32 + 𝑙4

2

2𝑙2𝑙4 , (7)

and substitute it in (6), which in return leads to

Freundenstein’s equation for four-bar linkage mechanism

shown on Fig. 3:

cos(𝜃1 − 𝜃2) = 𝐷1 cos 𝜃1 − 𝐷2 cos 𝜃2 + 𝐷3 . (8)

General form of Freundenstein’s equation is:

cos(𝜃1𝑖 − 𝜃2

𝑖) = 𝐷1 cos 𝜃1𝑖 − 𝐷2 cos 𝜃2

𝑖 + 𝐷3 ;

𝑖 = 1, 2, 3 . (9)

From there we can solve three linear equations using angle

values determined in (2) and (3) and calculate design

parameters Di, i=1,2,3. These design parameters are used to

calculate length values l2, l3, and l4. Length of link l1 is chosen

for example, based on characteristics of an index human

finger or any other assumption. These ratios are important

because they allow us to scale robotic finger but to keep same

relative movement between various links.

B. Transmission angle

Now, concept of transmission angle [5], needs to be

introduced as well, because that is another parameter, besides

aforementioned design parameters Di, i=1, 2, 3, that are used

in optimization method described in this paper. Let’s assume

that input torque T1 is acting on link O2A. That link in now

called input link.

Fig. 4. Representation of transmission angle in four-bar linkage

mechanism.

In Fig. 4, if O2A is the input link, torque T1 to the input link

is causing force 𝐹𝐵⃗⃗⃗⃗ , which is transmitted through the coupler

link AB. For sufficiently slow motions (where we can neglect

inertia forces), the force in the coupler link is pure tension or

compression and is directed along AB. For a given force in

the coupler link, the torque transmitted to the output link, T2

(about point O1), is maximum when the angle µ between

ROI 1.2.2

coupler link AB and output link O1B is 90º. Therefore, angle

ABO1 is called transmission angle.

It varies throughout the range of operation from acute

angle µ to obtuse angle π-µ.

According to Fig. 4 transmission angle can be calculated

by writing the cosine theorem for O1A using the triangles

O1AB and O1AO2 and equating the length O1A. It is expressed

in following form:

𝜇 = 𝑐𝑜𝑠−1𝑙12 + 𝑙2

2 − 𝑙32 − 𝑙4

2 − 2𝑙2𝑙1 cos(𝜋 − 𝜃1)

−2𝑙3𝑙4. (10)

Most favorable value of transmission angle is 90º and

recommended variations of transmission angle [5] is 90º±50º.

When transmission angle is 0º or 180º transmission of motion

is impossible. No torque can be realized on output link if

transmission angle is 0º and mechanism is at its dead center

position.

C. Transmission quality

The term transmission index [6] was introduced as a

generalization of the concept of transmission angle. It is one

of many performance indexes of one mechanism. For planar

four-bar linkages, the transmission index is shown to be the

sine of the transmission angle. Just like the transmission

angle, which varies with the configuration of the linkage, the

transmission index is also dependent on configuration. As a

global performance parameter that measure the force and

motion transmission of the linkage, transmission quality [7]

is used, which is defined in terms transmission index.

Transmission quality is suitable to evaluate mechanism

performance throughout its whole range of motion and is not

defined only to a local evaluation at a single configuration.

Transmission quality of four-bar linkage mechanism from

Fig. 4, is defined in following equation:

𝑧 = √1

𝜃11 − 𝜃1

3 ∫ 𝑠𝑖𝑛2

𝜃13

𝜃11

𝜇𝑑𝜃1. (11)

The complement [15] of the transmission quality, is

defined as:

𝑧′ = √1

𝜃11 − 𝜃1

3 ∫ 𝑐𝑜𝑠2

𝜃13

𝜃11

𝜇𝑑𝜃1 , (12)

and is called transmission defect which is an objective

function to be minimized, and conforms to:

𝑧 + 𝑧′ = 1 ; 0 < 𝑧′ < 1 . (13)

In this paper, link lengths, which yields minimum

transmission defect will be defined. Note that this parameter

is only one of many parameters that need to be taken into

account when designing underactuated robotic finger, and

despite the fact that best transmission of force and movement

is desired, lengths of links may differ from values calculated

here. It is important to keep in mind that these robotic hands

should be as light as possible, robust and in order to be

industry acceptable they need to be cost efficient.

It is also stated that with mechanisms that have reversal

motion, as robotic hand has (opening and closing of hand)

transmission angle must be investigated for both cases of

motion transmission but that will be scope of future research

because in this research only pinch and form grips are taken

into account, and in those, direction of forces acting upon

object of manipulation are only in direction of closing of

robotic hand and that direction will be examined.

In next chapter, analysis described above, will be used on

optimization of design of CMSysLab underactuated robotic

hand.

III. SYNTHESIS OF OPTIMAL PLANAR FOUR-BAR LINKAGE

MECHANISM FOR CMSYSLAB UNDERACTUATED ROBOTIC

FINGER

When designing transmission mechanism, the crucial issue

is selection of mechanism and dimensioning of chosen

mechanism. Optimization of planar four-bar linkage [8]

mechanism is carried out, as mentioned in previous chapter,

with regard to three positions of input and output links which

yields three linear equations. These are solved using

Freudenstein’s equation. Later, optimization of force

transmission is carried out using transmission defect as

objective function to be minimized. The linkages connected

in series are synthesized by starting from the four-bar linkage,

which moves the distal phalanx.

A. Synthesis of the four-bar linkage O3, O2, P2, P3

For synthesis of the function generating four-bar linkage

O3, O2, P2, P3, shown in Fig. 5, we used method described in

section II.

Freudenstein's equation for shown mechanism can be

expressed in the form:

cos(𝜃3𝑖 − 𝜃4

𝑖) = 𝐷1 cos 𝜃3𝑖 − 𝐷2 cos 𝜃4

𝑖 + 𝐷3 ,

𝑖 = 1, 2, 3.

(14)

Design parameters Di, i=1, 2, 3, based on (7) are calculated

as:

𝐷1 =𝐿2

𝑐2

; 𝐷2 =𝐿2

𝑎2

; 𝐷3 =𝐿22 + 𝑎2

2 − 𝑏22 + 𝑐2

2

2𝑎2𝑐2

. (15)

The four-bar linkage shown in Fig. 5, consists of links a2,

b2, c2 of four-bar linkage: O2P2, P2P3 and P3O3 and medial and

distal phalanges L2 and L3 of underactuated robotic finger. As

described in [1], during motion phalanges move until they

come in contact with object that needs to be manipulated.

Phalanx that comes in contact with object stops moving, in

our case medial phalanx L2, which is fixed on Fig. 5, and

distal phalanx L3 can move until it reaches object or

mechanical hardstop which constricts its movement.

Fig. 5. Representation of four-bar linkage O3, O2, P2, P3.

ROI 1.2.3

Angles 𝜃3𝑖 and 𝜃4

𝑖 for i=1, 2, 3 are input and output angles

of mechanism, respectively.

Many of design parameters on Fig. 5 are empirically

acquired, based on actual human hand proportions.

According to the proposed mechanical design of the finger,

the design parameters are α = 90º, α1 = 20º, β1 = 7.5º and

γ1 = 47º. With that in mind, pairs of angles for the starting and

final position of links a1 and c1 are easily acquired. Values of

those angles are (𝜃31, 𝜃4

1) = (82.5º, 70º) for starting position

and for final position (𝜃33, 𝜃4

3) = (133º, 160º).

Freudenstein's equation (14) can be solved when three

positions ①, ② and ③ of the input link a2, and

corresponding three positions ①, ② and ③ of the output

link c2 are known. Angle pairs, determined above, are to be

substituted in (14), and by solving three linear equations we

obtain design parameters Di, i=1, 2, 3, that are used in (15) to

calculate link lengths.

Since only two of the three pairs of angles required by the

Freudenstein’s equations are assigned as design specification

of the function generating four-bar linkage ABCD, an

optimization procedure in terms of force transmission has

been developed by varying values of (𝜃32, 𝜃4

2) during process

of optimization.

These values of link lengths are then substituted in

transmission angle equation for four-bar linkage mechanism

shown on Fig. 5:

𝜇1 = 𝑐𝑜𝑠−1𝐿22 + 𝑎2

2 − 𝑏22 − 𝑐2

2 − 2𝐿2𝑎2 cos(𝜋 − 𝜃3)

2𝑏2𝑐2. (16)

Transmission defect for mechanism on Fig. 7 is defined as:

𝑧′ = √1

𝜃33

− 𝜃31

∫ 𝑐𝑜𝑠2

𝜃33

𝜃31

𝜇1𝑑𝜃3 . (17)

Substituting (16) in (17) gives the value of 𝑧′. If it is

minimum value, calculated lengths of links will be optimal,

if not, then angle values (𝜃32, 𝜃4

2) should be varied in a specific

range until minimum value of 𝑧′ is found.

-------------------------------------------------------------------------

Proposed algorithm

-------------------------------------------------------------------------

Require: Defining the base phalanx length L2 and pairs of

minimum and maximum values of the input and output angles

(𝜃31 , 𝜃4

1) and (𝜃33, 𝜃4

3) of four bar linkage

Step 1: Substitute angle pairs into Freudenstein’s equation

Step 2: FOR (defined increment)

Symbolic solving the system of three

equations, resulting in equations for lengths

a2, b2 and c2, which are function of angles

(𝜃32 , 𝜃4

2);

end FOR

Step 3: FOR (defined increment)

(𝜃31, 𝜃4

1) < (𝜃32, 𝜃4

2) < (𝜃33, 𝜃4

3)

Solve:

cos(𝜃3𝑖 − 𝜃4

𝑖) = 𝐷1 cos 𝜃3𝑖 − 𝐷2 cos 𝜃4

𝑖 + 𝐷3 , 𝑖 = 1, 2, 3.

Calculated values store in predefined matrices

A, B and C

Solve:

𝑧′ = √1

𝜃33 − 𝜃3

1 ∫ 𝑐𝑜𝑠2

𝜃33

𝜃31

𝜇1𝑑𝜃3 .

Calculated values store in predefined matrix D

end FOR

Step 4: WHILE z’ ~ min (z’)

Go through matrices A, B, C and D

end WHILE

Step 5: Obtain values of a2, b2 and c2 for z’ = min (z’) ---------------------------------------------------------------------------------

Values of link lengths obtained from optimization process

are shown in Table III and Fig. 6.

TABLE I

INPUT PARAMETERS FOR OPTIMIZATION ALGORITHM USED FOR

OPTIMIZATION OF THE FOUR-BAR LINKAGE O3, O2, P2, P3

Minimum and maximum values of input and output angles

𝜃31 82.5º 𝜃3

3 133º

𝜃41 70º 𝜃4

3 160º

TABLE II STARTING VALUES OF PARAMETERS FOR OPTIMIZATION ALGORITHM

USED FOR OPTIMIZATION OF THE FOUR-BAR LINKAGE O3, O2, P2, P3

Starting values of parameters to be optimized with limits of

values

𝜃32 107.75° ± 25°

𝜃42 115° ± 45°

L2 37.5 (fixed value)

a2 23mm ± 10mm

b2 36mm ± 10mm

c2 14mm ± 5mm

Z’ 0.103

TABLE III

OBTAINED PARAMETERS FROM OPTIMIZATION

z’=0.02526 L2 37.5 a2 28.361 b2 36.993 c2 15.82

Fig. 6. Optimized parameters of four-bar linkage O3, O2, P2, P3.

On Fig. 6, four-bar mechanism of grey color is

proportional to starting dimensions of link lengths. Green

four-bar mechanism is shown with calculated link lengths. It

is obvious that there is difference between calculated values

after optimization and starting values. It is because starting

values are empirically acquired based on human finger

proportions and many more parameters like space limitations,

etc. All those parameters need to be taken into account when

designing underactuated robotic finger and not just

transmission quality as described in this paper. It is obvious

that this is iterative process and it needs to accommodate

many criteria in order to produce optimal result.

Now dimensions of links of second four-bar linkage will

be addressed.

ROI 1.2.4

B. Synthesis of the four-bar linkage O2, O1, P1, P2’

After optimization of four-bar transmission mechanism of

medial phalanx it is important to do the same with four-bar

transmission mechanism of proximal phalanx.

For synthesis of the function generating four-bar linkage

O2, O1, P1, P2’, shown in Fig. 7, we used same method as for

aforementioned four-bar linkage. Freudenstein's equation for

shown mechanism can be expressed in the form:

cos(𝜃1𝑖 − 𝜃2

𝑖) = 𝐷1 cos 𝜃1𝑖 − 𝐷2 cos 𝜃2

𝑖 + 𝐷3 ,

𝑖 = 1, 2, 3. (18)

Design parameters Di, i=1, 2, 3, based on (7) are calculated

as:

𝐷1 =𝐿1

𝑐1; 𝐷2 =

𝐿1

𝑎1

; 𝐷3 =𝐿12 + 𝑎1

2 − 𝑏12 + 𝑐1

2

2𝑎1𝑐1 . (19)

Fig. 7. Representation of four-bar linkage O2, O1, P1, P2’.

Parameters shown on Fig. 7: L1 is the length of proximal

phalanx of the finger, a1, b1 and c1 are lengths of links of four-

bar linkage: O1P1, P1P2’ and P2’O2, angles 𝜃1𝑖 and 𝜃2

𝑖 for i=1,

2, 3 are input and output angles of mechanism, respectively.

As already shown, (18) can be solved when three positions

①, ② and ③ of the input link a1, and corresponding three

positions ①, ② and ③ of the output link c1 are predefined.

Many of design parameters on Fig. 7 are empirically

acquired, based on actual human hand proportions.

According to the proposed mechanical design of the finger,

the design parameters are α2 = 10º, β2 = 60º and γ2 = 43º. With

that in mind, pairs of angles for the starting and final position

of links a1 and c1 are easily acquired. Values of those angles

are (𝜃11, 𝜃2

1) = (80º, 30º) for starting position and for final

position (𝜃13, 𝜃2

3) = (137º, 171º). These are to be substituted in

(18), and by solving three linear equations we obtain design

parameters Di, i=1, 2, 3, that are used in (19) to calculate link

lengths. These values are then substituted in transmission

angle equation:

𝜇2 = 𝑐𝑜𝑠−1𝐿12 + 𝑎1

2 − 𝑏12 − 𝑐1

2 − 2𝐿1𝑎1 cos(𝜋 − 𝜃1)

2𝑏1𝑐1. (20)

Transmission defect for mechanism on Fig. 7 is defined as

𝑧′ = √1

𝜃13− 𝜃1

1 ∫ 𝑐𝑜𝑠2

𝜃13

𝜃11

𝜇2𝑑𝜃1 . (21)

Substituting (20) in (21) gives the value of 𝑧′. If it is

minimum value, calculated lengths of links will be optimal,

if not, then angle values (𝜃1, 𝜃2) should be varied in a specific

range until minimum value of 𝑧′ is found, the same way as

with previous four-bar linkage. Values of link lengths

obtained from optimization process are shown in Table VI

and Fig. 8.

TABLE IV INPUT PARAMETERS FOR OPTIMIZATION ALGORITHM USED FOR

OPTIMIZATION OF THE FOUR-BAR LINKAGE O2, O1, P1, P2’

Minimum and maximum values of input and output angles

𝜃11 80 𝜃1

3 137º

𝜃21 30º 𝜃2

3 171º

TABLE V STARTING VALUES OF PARAMETERS FOR OPTIMIZATION ALGORITHM

USED FOR OPTIMIZATION OF THE FOUR-BAR LINKAGE O2, O1, P1, P2’

Starting values of parameters to be optimized with limits of

values

𝜃12 108.5° ± 28°

𝜃22 100.5° ± 70.5°

L1 37.5 (fixed value)

a1 32mm ± 10mm

b1 60mm ± 10mm

c1 15mm ± 5mm

Z’ 0.081

TABLE VI

OBTAINED PARAMETERS FROM OPTIMIZATION

z’=0.02993

L1 64.5 a1 41.83

b1 60.554 c1 16.39

Fig. 8. Optimized parameters of four-bar linkage O2, O1, P1, P2’.

On Fig. 8, with grey color, four-bar mechanism with

starting link lengths is shown. Green color represents new

four-bar mechanism with calculated link lengths.

Previously described method of optimization of four-bar

linkage geometry is useful for process of designing linkage

based underactuated robotic hand, because calculated values,

now can be used as starting values for later designing

processes which will use another set of criteria for acquiring

optimal geometry of underactuated finger based on many

criteria and not just one described in this paper.

IV. CONCLUSION

In this paper, a method for obtaining optimal lengths of

links based on transmission, quality in a four-bar linkage

mechanism, was presented. This kind of analysis is important

so that researchers and designers of underactuated robotic

hands can design proper underactuated finger that can

transmit sufficient force onto object that been manipulated

with.

As shown, this is only one of many parameters that need to

be addressed in order to design proper, robust and dexterous

enough robotic hand that is able to accommodate all

requirements placed upon it by industrial assembly

operations. Some of those requirements are:

Precision: assembly process, especially when we take into

consideration precise assemblies in auto or aerospace sectors

of manufacturing engineering, require high precision and

ROI 1.2.5

accuracy of placing of different parts in a assembly.

Strength of grip: it is needed in order for robotic hand to

be able to counteract contact forces when handling objects.

Rigidity and errors that are imposed from lack of rigidity is

important factor to take into account. Errors and lack of

rigidity are direct consequence of clearances that exist in

assemblies.

Access to the zone of assembly: access to the zone in

which assembly of parts needs to take place in required

position and orientation.

ACKNOWLEDGMENT

This research work is supported by the Serbian Ministry

for Education, Science and Technology Development

through the projects titled 'Smart Robotics for Customized

Manufacturing', grant No.: TR35007, and 'Development and

Experiments of Mobile Collaborative Robot With Dual-Arm',

grant No.: 401-00-00589/2018-09, which is jointly realized

by Anhui University of Technology, Ma'anshan, Anhui, and

Tsinghua University, Beijing, from one side, and Institute

Mihajlo Pupin – Belgrade (IMP), Faculty of Mechanical

Engineering, University of Belgrade (MFB), and Faculty of

technical sciences of Novi Sad, University of Novi Sad

(FTN), from the other side, supported by a cluster of

industrial partners from both sides, as a bilateral scientific

project of high national relevance with the People’s Republic

of China.

REFERENCES

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